If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.

Welding rig question

04-01-2010, 09:22 PM

I am building a flatbed for my service truck. I will be using the bed as a table top and will have tables attached to bed. I am looking for advice as how to attach the bed to the frame without the electrical current running through my trucks electrical system. The frame to bed mount will have to be heavy duty. Any advice would be very helpful and most appreciated. I have searched past threads and havent found any info on this.

UHMW would be about the only way I could think of doing it that it would work and actually last. But you would need to machine it to completely isolate the bolts from the deck frame AND the truck frame, you would also need UHMW washers. Sounds like a lot of work for something that doesn't give anyone any trouble. Just don't hook your ground clamp on the front bumper and weld on the work plate and you will be fine. Electricity is lazy, it ALWAYS takes the shortest path, ground directly to your work or at least directly to your work plate.

I have personally installed over 20 welding skids and 8 or 10 welding decks for customers, mostly on new diesel trucks of every brand as well as a few gas trucks. The only problem anyone had was one guy had some weird arcing between the hinges for the work table and the skid. He thought it was a faulty reel, but it turned out his brand new Lincoln 305G had a wire grounding out on the case. It essentially made the welder case hot and since it was bolted to the skid it made the skid hot as well, he got that fixed under warranty and no more problems. Even when he had the problems with the welder it never affected his diesel truck, and the mounting bolts between the skid and truck were not isolated.

Comment

I’ve always used wood between the rails of the flatbeds and truck frame.

In this case I was thinking of using the UHMW like flatbar. I’ve had good luck cutting UHMW with a skilsaw, drill a couple holes in it, bolts, flat washers against the UHMW, and nylock nuts on the rails, and frame.

Caution!
These are "my" views based only on “my” experiences in “my” little bitty world.

Comment

I was told by a contractor who I sub for that Georgia DOT requires this to be done, along with all of the other ridiculous stuff. I looked at 2 of his service trucks that are equipped to weld and neither were mounted like that. Maybe he just needed something to talk about. I have worked off a trailer for 2 years and never had any problem. Thanks for clearing this up for me. I am trying to locate this official DOT regulation but cant find any info on this.

Comment

I was told by a contractor who I sub for that Georgia DOT requires this to be done, along with all of the other ridiculous stuff. I looked at 2 of his service trucks that are equipped to weld and neither were mounted like that. Maybe he just needed something to talk about. I have worked off a trailer for 2 years and never had any problem. Thanks for clearing this up for me. I am trying to locate this official DOT regulation but cant find any info on this.

Sounds like someone is blowing some smoke.
It can be done but I really don't think it's necessary.

Comment

I was told by a contractor who I sub for that Georgia DOT requires this to be done, along with all of the other ridiculous stuff. I looked at 2 of his service trucks that are equipped to weld and neither were mounted like that. Maybe he just needed something to talk about. I have worked off a trailer for 2 years and never had any problem. Thanks for clearing this up for me. I am trying to locate this official DOT regulation but cant find any info on this.

Keep in mind that electronics for the most part aren't affected by the electrical current unless they become part of the circuit. So if you have your ground from you welder to your work and work lead from you welder to your work then there's no reason for the current to go off and get into trouble. Current is like a teenager most of the time. It will take the path of least resistance. Good cables and good connections will keep your current going only where it's supposed to go.

Comment

I was told by a contractor who I sub for that Georgia DOT requires this to be done, along with all of the other ridiculous stuff. I looked at 2 of his service trucks that are equipped to weld and neither were mounted like that. Maybe he just needed something to talk about. I have worked off a trailer for 2 years and never had any problem. Thanks for clearing this up for me. I am trying to locate this official DOT regulation but cant find any info on this.

If this is true, have him cite the article, chapter, and verse. There would then be specific instructions, including materials, regarding procedure.

"Bonne journe'e mes amis"

Comment

I've put 4 welding rigs together for myself over the years, and have never isolated the bed. I don't see why you couldn't do it, but why bother? My first rig I used wood between the frame rails and the bed frame, but nowadays I just use square tubing. Makes it easier to run the wiring for various applications.